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LIBRARY OF CONGRESS, 1 



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! UNITED STATES OF AMERICA. \ 

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# 



JOSEPH HENRY 

AND THE 

MAGNETIC TELEGRAPH. 


AN ADDRESS 

DELIVERED AT PRINCETON COLLEGE, JUNE 10, 1885, 

BY 

V EDWARD N.DICKERSON, LL.D. 


"SI MONUMENTUM QU.ERIS CIRCUMSPICE." 


NEW YORK 
CHARLES SCRIBNER'S SONS 

1885 



LIBRARY OF CONGRESS, 

PRESENTED BY 

UNITED STATES OP AMEEIOA. 



JOSEPH HENRY 



MAGNETIC TELEGRAPH. 



AN ADDRESS 

DELIVERED AT PRINCETON COLLEGE, JDNE 16, 1885, 



BY 



EDWARD N, DICKERSON, LL.D. 



"SI MONUMENTUM QUARTS CIRCUMSPICE. 



NEW YORK 
CHA.R,LES SCRIBNER'S SONS 

18S5 



<*;> 



College of New Jersey, 
Princeton, N. J., June 19, 1885. 

My Dear Sir: 

Immediately after the delivery of your paper 
on the discoveries of Dr. Joseph Henry, I ex- 
pressed my strong personal desire to see it pub- 
lished. 

I find that the College is at one with me in this 
wish. 

We should like to have so comprehensive a 
paper circulated in our day, and handed down 
to posterity. 

I am yours ever, 

JAMES McCOSH. 

Edward N. Dickerson, LL.D. 



New York, June 22d, 1885. 
My Dear Sir : 

I take pleasure iu furnishing to Princeton Col- 
lege my address presenting the memorial tablet of 
Professor Henry. I have added to it an appendix 
of notes supporting the statements contained in it, 
which I trust will prove satisfactory. 

It is a labor of love for me to do anything 
tending to present our great and beloved friend to 
his own age, and to posterity, in his true propor- 
tions. His achievements seemed to him so easy 
to perform, that he never looked upon them as 
exhibiting auy great power ; and he therefore 
involuntarily shrank from that praise to which 
he was so eminently entitled, and from conspic- 
uously exhibiting his results before the world. 
He preferred to defer to the judgment of posterity, 
and to submit his reputation to the ordeal of 
time, which, like a simple acid, eats away the baser 
metal, and leaves the pure gold free from its asso- 
ciation. 

With many thanks to you for the compliment 
implied in your request, 

I am, sir, very truly, 

Your obedient servant, 

EDW. N. DICKERSON. 
President McCosh, 

Princeton College. 



MEMORIAL ADDRESS 

DELIVERED BY 

EDWARD N. DICKERSON, LL.D., 

PRESENTING TO PRINCETON COLLEGE A TABLET DESIGNED TO 

COMMEMORATE THE CONTRIBUTIONS TO THE 

ELECTRIC TELEGRAPH OF 

JOSEPH HENRY. 



Mr. President and Gentlemen, Trustees of the 
College of New Jersey : 

The pleasing but sad duty has been assigned to 
me of presenting to you this memorial tablet of 
the beloved master, who once shed the lustre of his 
genius over this ancient seat of learning, and once 
attracted to its classic shades, allured by his great 
reputation, pilgrims from all lands, to drink from 
the living font of knowledge, ever replenished 
and refreshed by his ceaseless contributions. 

I commit this monument to your tender care. 
May it ever remain enshrined in this beautiful 
temple. May its presence encourage those, and 
the successors of those, to whom he delivered his 
torch of science, ablaze with a light which had 



6 PROFESSOR HENRY AND THE 

penetrated to the farthest ends of the earth, to 
tend that sacred flame; so that when they shall 
transmit it to their successors, it shall still be 
borne high aloft in the upper atmosphere of pare 
truth, with still increasing lustre — a guiding 
beacon to the wayfarer, wandering and astray 
in the gloomy valleys of ignorance — those deep 
defiles, where the shadows seem ever darkening 
by contrast with the brightening mountain tops 
illumined by the rising sun of knowledge. 

May it inspire the ingenuous youth, who in the 
thronging years of the future shall gather about 
these altars, to search the character and achieve- 
ments of the great master; that they may be taught 
by him how to study; how to think; how to work; 
how to live; and how to die. 

May it continue to remind those who annually 
are attracted here to witness the evidences of the 
growth of knowledge, as they are exhibited in the 
commencement seasons, that once this college was 
honored by the ministrations of Joseph Henry, 
an American, who, with means created almost 
wholly by himself, rivalled the achievements of 
the greatest scientists of the old world, working 
with the resources of nobly-endowed institutions, 
and encouraged by the bounty of Kings; and for 
years was ever a leader in the vigorous attack 
upon the arcana of nature, made by the champions 
of science in the early years of this century. 



MAGNETIC TELEGRAPH. 



For those of us who enjoyed the happiness of 
knowing him well, and loving him dearly, no 
sculptured marble is needed to stir our hearts, or 
keep fresh in our memories that noble presence, 
which at once charmed and satisfied our senses. 
Nor, if the chisel of the artist were guided by the 
genius that once inspired Phidias, would it be 
capable of fixing upon dull, cold marble more than 
one of the almost infinite variety of expressions 
revealing to the world without the exalted being 
within. 

But to those who have never seen him, or having 
seen him have never known him, and to those who 
shall come after us, it will be something to look 
upon this marble, and inspired by the thoughts he 
uttered, and the deeds he did, contemplate its calm 
expression, and imagine what must have been the 
living man. 

In the year 1839, nearly half a century ago, 
brought here as a student, I first saw Professor 
Henry. I remember it well — the time, the place, 
and the surroundings. Boyish imagination had 
pictured the great discoverer as a venerable man, 
bowed down with the toil of years, bearing the 
furrows, with which overtasked nature revenges 
herself, traced upon his brow : such a person, 
perhaps, as the artist has presented to us in the 
familiar picture of Humboldt in his library. 



8 PROFESSOR HENRY AND THE 

How different the reality ! In the maturity of a 
perfect manhood he stood : 

" A combination, and a form indeed, 
Where every God did seem to set his seal, 
To give the world assurance of a man." 

His clear and delicate complexion, flushed with 
perfect health, bloomed with hues that maidenhood 
might envy. Upon his splendid front, neither 
time, nor corroding care, nor blear-eyed envy, 
had written a wrinkle, or left a cloud ; it was 
fair and pure as monumental alabaster. His 
erect and noble form, firmly and gracefully 
poised, would have afforded to an artist an ideal 
model for an Apollo. The joy of conflict and of 
triumph beamed from his countenance — a conflict 
in which, for years, he had struggled with the 
phantoms that guard the hidden treasures of 
nature, and had ever been victorious. And above 
all, surmounting all, infinite charity and gentle- 
ness — like the charity and gentleness of a loving 
mother for her erring children. 

To him the youthful student bowed down in 
profound admiration. To him, and to his memory, 
for nearly fifty years, he has clung with ever-in- 
creasing love and affection. And now that seven 
years have passed away since death severed the 
bond strengthened by a life-time of intimacy, 
he recurs with fondest memories to the many 
happy occasions when it was his good fortune 



MAGNETIC TELEGRAPH. 



to spend hours in sweet and instructive converse 
with this gifted mortal, to whom the whole book of 
nature was an open volume, out of which he ever 
read lessons of wisdom, and beauty, and truth. 

As Professor Henry appeared in 1839, so he con- 
tinued till 1847, with but little change in the 
physical man — only that change, which, like the 
changes in the early autumn, lightly touched with 
tints of exquisite beauty the mature growth of 
spring-time and summer ; and then, with extreme 
reluctance, he departed from Princeton, called by 
his country to lay down the arms with which, as 
a soldier in the ranks, he had been waging his war- 
fare against ignorance, and take command of the 
intellectual forces to be summoned and organized 
by him in the same glorious cause. 

Born in the dying moments of the eighteenth 
century, his age was marked by the numbers 
denoting the years of the nineteenth. Like the 
century, with whose growth his growth kept 
pace, he had developed with almost unexampled 
rapidity; and at the age of thirty-two, when he 
took his chair here, although "he was but a 
" youth, and ruddy, and of a fair countenance," 
and was armed only with a simple sling of his 
own construction, and pebbles from the brook 
of nature, he was equal to the trained warriors 
of maturer growth and superior armor, waging 
war against the GJ-oliah that guarded the unex- 



10 PROFESSOR HENRY AND THE 

plored regions of nature's secrets ; and like the 
great king of Israel, after the brunt of the battle 
was over, he came to be leader of the hosts, who 
once had been tending only a "few sheep in the 
wilderness." 

Let us contemplate for a moment the intellectual 
stature of our departed teacher, considered merely 
as an investigator of natural laws, and measured by 
the standard established by the intellectual world. 

It is in the order of nature that the intermittent 
progress of humanity is made under the guidance 
of gifted men, appearing from time to time, who 
push forward the outposts of truth, whether in 
morals or physics, calling upon their fellow-men 
to hasten and occupy the newly-conquered fields. 
The names of such men are few, and are writ- 
ten upon the rolls of fame. Their glory be- 
longs to no nation, but to all mankind. Some- 
times simultaneously and in different parts of the 
world two such appear, who seem to have 
been cast in similar moulds, lest perchance one 
might die or fail, and progress stand still. Such 
men were Henry and Faraday, whose intellects 
were moulded with the same capacities, and who 
worked out their tasks in the same spirit. If 
either one had died before his work was done, the 
other was capable of doing it ; and, in fact, both 
in many cases struck out the truth, each uncon- 



MAGNETIC TELEGRAPH. 11 

scious that the twin thought had been born in the 
brain of the other. 

To those devoted friends and admirers of Fara- 
day, who delight in singing his well-earned praises, 
and who best comprehend his achievements, it 
seems that his discovery that electricity might 
be produced from magnetism was his grandest 
result. Upon it depends many of the most 
important applications of electricity to the uses 
of man ; and in the near future many more 
are coming. Tyndall, the successor of Faraday, 
does not restrain his enthusiasm when he contem- 
plates this achievement. ' ' I cannot help think- 
ing," says he, "while I dwell upon them, that 
" this discovery of magneto-electricity is the 
" greatest experimental result ever obtained by 
" an investigator. It is the Mont Blanc of Far- 
" aday's own achievements. He always worked 
" at great elevations, but higher than this he never 
" subsequently attained."* 

Let us accept the standard, and apply it to 
Henry; let the achievement measure the power 
of the man. 

In November, 1831, Faraday read before the 
Eoyal Society his memorable paper "On the 
Evolution of Electricity from Magnetism," 
illustrated by drawings of the apparatus, in 
which Figure 1 is the compound "spool," dis- 

* See Appendix, Note A. 



12 PROFESSOR HENRY AND THE 

covered by Henry in 1828, and which Faraday 
used in making his discovery.* No publica- 
tion referring to this paper had reached this 
country till April, 1832, when a vague reference, 
made to it in the " Annals of Philosophy " was seen 
by Henry, which led to his publication of July, in 
" Silliman's Journal" where he gave a full ac- 
count of this great discovery, made by himself 
before he heard of Faraday's work, which, when 
compared with Faraday's paper of November, 
exhibits Faraday's experiment for solving the 
problem. When he wrote his paper, Henry, 
mislead by the imperfect statement in the 
"Annals of Philosophy ," supposed that his experi- 
ment had differed from Faraday's, but was un- 
deceived when the full publication reached him. 
In 1831, a teacher in the Albany Academy was 
very remote from London, and the Eoyal Society. 

In that same year, and in the same few weeks, 
Faraday first, and Henry after him, independently 
made the discovery of magneto -electricity; " the 
" greatest experimental result ever obtained by 
" an investigator," in the opinion of Tyndall.f 

In the same field, and during the same years, 
were the other great scientists of the world, study- 
ing the same subject : Ampere, Arago, Oersted, 
Davy, and a host of others; but these two did it, and 

* See Appendix, Note B. 
t See Appendix, Note C. 



MAGNETIC TELEGRAPH. 13 

not the others ; and Henry did it by devices of his 
own invention, unaided by anything which Faraday 
had discovered or produced, while Faraday used 
Henry's electro-magnet in performing his most 
important experiment. 

The towering heights which were scaled by the 
daring spirit of Faraday from the East, were at the 
same time surmounted from the West by our own 
countryman. Both were climbing from opposite 
sides at the same time, and neither was conscious 
of the other's efforts till both stood, face to face, 
upon the summit. Had Henry been furnished 
with the corps of trained mountain guides, and 
Alpine- stocks, such as attended Faraday in his 
ascent, perhaps his foot would have first trodden 
the peak, and Prof. Tyndall's song of triumph have 
been addressed to him. 

But when we compare Henry with Faraday, 
who is the acknowledged unit of comparison, the 
accidental conditions under which both existed 
and worked must be known, or justice cannot be 
done. Electrical science was the field to which 
both spontaneously directed their studies. Its 
mysteries at once excited curiosity, and baffled re- 
search. Its most obvious phenomena had only for 
a short time been recognized, and everything was 
to be learned. What they did in that science, not 
only constitutes the greater part of their claims 
to reputation as investigators, but is almost the 



14 PROFESSOR HENRY AND THE 

whole of our present knowledge of magneto -elec- 
tricity. 

But how superior in every respect, except in 
God-given intellect, was the equipment of Fara- 
day. He was eight years older than his rival. In 
the year 1813 he was appointed " assistant" in 
the laboratory of the Royal Institution, under Sir 
Humphrey Davy, then one of the foremost scien- 
tists of the world, who, attracted by Faraday's 
genius, was directing his studies and forming his 
mind. At that time Henry was but thirteen 

YEARS OLD. 

In the next twelve years Faraday was at 
work, with all the resources of the Royal 
Institution, under the instruction of the great 
Davy, in acquiring the knowledge with which he 
was armed when he began his original investiga- 
tions ; while Henry, during that same period, was 
struggling unaided for such education as might 
be obtained from the scanty resources of a country 
town ; and with that proud independence, ever 
so marked a feature of his character, was sup- 
porting himself by teaching to others a part of 
that which he was learning himself. 

In 1825, Faraday had so improved his great op- 
portunities, that at the age of thirty-four he was 
appointed " director of the laboratory " of the Royal 
Institution, where everything that science could 
suggest, and money procure, was at his command 



MAGNETIC TELEGRAPH. 15 

in aid of research. Henry was then a private tutor 
in a distinguished family at Albany ; studying 
mathematics in hours when his duties to his 
pupils had ceased, and when other young men 
might have thought they had earned the right to 
relaxation and enjoyment. 

In 1824, before Henry ever had in his hands 
any instruments for research in electricity, Fara- 
day, thus trained and equipped, began his attack 
upon the problem of magneto-electricity and 
failed ; and in 1830 it was not yet solved. 

The discoveries of deductive science need no ap- 
paratus. They are made and matured in the 
brain ; and to record them is the only physical 
incident to their existence or development. 
Plato would have looked with disgust and 
contempt upon a laboratory ; and would have 
scorned the suggestion that time, or place, or 
physical surroundings, could affect the workings 
of his mind, or influence his deductions. But the 
new philosophy, which has changed the face of the 
world, is of no such ethereal nature. It is born in 
observation of physical things; it is nurtured upon 
experiments that cost money, and time, and labor; 
its maturity is in perfected arts, and in things 
to be seen, and handled, and enjoyed by the 
senses; its end is to subordinate the blind forces of 
nature to the uses of man — to mitigate the ills, and 
multiply the joys of life. They who are the ser- 



16 PROFESSOR HENRY AND THE 

vants of this philosophy, must be provided with 
materials with which to reproduce, in miniature, 
the conditions that exist in nature in grander pro- 
portions, or they cannot ask the questions whose 
answers they are seeking; and, other things being 
equal, he who is well provided with all these need- 
ful things, has an immense advantage over another 
who lacks them. 

For thirteen years Faraday had been pursuing his 
investigations amply supplied, and was in the full 
career of successful experiment when, in 1826, his 
great rival first looked upon the course over which 
he was to run ; and even then Henry had to depend 
upon the meagre facilities of the Albany Academy, 
and the voluntary assistance of an appreciative 
physician, Dr. Philip Ten Eyck, of Albany — a 
name to be held in grateful remembrance by all 
who feel a pride in the achievements of the great 
scientist, whose early efforts were assisted, and 
whose hopes encouraged, by this enlightened 
friend. 

With such a beginning as this, who could expect 
that the young aspirant for fame should ever 
overtake his great leader in the friendly contest ? 
And when he did overtake him, and in some im- 
portant investigations surpass him, who shall deny 
that Henry, as a physical investigator, was the 
equal of him above whom it is conceded no other 
man has risen in this century! 



MAGNETIC TELEGRAPH. 17 

In still further pursuing his researches into the 
subtle phenomena of electricity, Henry made, here 
in Princeton, another capital discovery, this time 
in advance of Faraday, which forms an important 
element in the science of electricity. It is to 
be found detailed in any school book, under the 
name of " Henry's Coils." His wonderfully elab- 
orate investigations will be remembered by the 
students of that day; as it was conducted in part 
in the open air. Wires stretched across the cam- 
pus, in front and in rear of Nassau Hall, were 
the means by which the questioner was cross- 
examining nature, and wresting from her reluct- 
ant grasp her hidden secrets. At that time tele- 
graph wires did not exist ; and those fine lines 
traced across the sky, excited the liveliest interest 
in the students, whose fantastic guesses as to their 
significance were the cause of much pleasantry in 
the idle hours. 

In the course of these investigations it was also 
the good fortune of our scientist to first discover 
the very curious phenomenon of "self induction," 
as it is now called, which plays so important a 
part in the creation and use of electric currents on 
wires, sometimes injuriously and sometimes ben- 
eficially. Without the knowledge of its laws no 
duplex or quadruplex telegraph could be practically 
operated; with that knowledge it can be neutral- 
ized when it is injurious, and made available when 



18 PROFESSOR HENRY AND THE 

useful. The brilliant spark which follows the 
pulling of the pendant, attached to an electric 
lighter for inflaming a gas jet, now in common 
use, is one of the valuable practical applications 
of this principle so discovered. 

In contemplating the discoveries of the scientist 
there are two aspects in which they present them- 
selves. In one view we consider merely the diffi- 
culty of the achievement; in the other, the value 
of the result to mankind. The first view is ob- 
vious when the thing is done; the other is to be re- 
served for a future day, when all the consequences 
have followed the original cause. The first view 
is that which measures the power of the man — 
just as the lifting of a huge weight by some Her- 
cules exhibits his strength, even though the 
thing done may be, or may seem to be, useless. 
The capital discoveries I have named, made by 
Henry and Faraday, exhibited the giant's strength 
when they were made, and measured the men 
who made them. They were found at great 
depths below the surface, where mental vision can 
only penetrate by the aid of lenses, constructed in 
advance, in accordance with the very laws for 
whose discovery they are needed — creations of the 
scientific imagination, and called scientific hy- 
potheses. In such creations Professor Henry was 
excelled by no man. 

Time will not permit even a hasty review of all 



MAGNETIC TELEGRAPH. 19 

the scientific labor done by Professor Henry at 
Princeton, during those years when his chief duties 
were instruction, and when he had only a portion 
of his time in which to work for mankind and for 
reputation ; and I must be content with a passing 
glance at a part of it. 

Among those wires which were strung across 
the campus in 1835, was one used for a mag- 
netic telegraph between the professor's home and 
his laboratory in the Philosophic Hall; and that 
telegraph line was the first in the world in which 
the galvanic circuit was completed through the 
earth— one end of the single wire-circuit ter- 
minating in the well at the house, and the other 
in the earth at the Hall. Steinheil, in Munich, 
in 1837, worked his electric telegraph in the 
same way by a single line wire, using the earth 
as part of the circuit, over much longer distances; 
but it was first done in this campus. 

Nearly a century earlier our great countryman, 
Franklin, had drawn from a surcharged thunder- 
cloud, upon the string of a kite, in a pouring shower 
of rain, the lightning of heaven, and had demon- 
strated its identity with the puny spark of an 
electrical machine; and with that capital experi- 
ment his fame is more closely associated than with 
any other of the great truths he discovered. In 
these grounds that experiment was amplified, and 
still further results obtained, by the man for 



20 PROFESSOR HENRY AND THE 

whom the mantle of Franklin had been waiting 
all those years, and who was the only American 
whose stature would not have been dwarfed by 
assuming it. 

From the clear, blue sky, with two kites, one 
above and assisting the other, held by a delicate 
wire wound on an insulated reel, Professor Henry 
drew down streams of brilliant sparks, intensified 
by the self-induction of the wire itself; thus prov- 
ing the electrical relations of the earth and its 
envelope. So, a child's plaything in the hands 
of a master, reveals the hidden mysteries of the 
universe. 

Away beyond the distant horizon we see at 
times a quivering illumination of the sky, but hear 
no thunder. How shall that phenomenon be ques- 
tioned ? Fifty years ago, Henry converted the 
metallic roof of his house into a great induc- 
tive plate, by soldering to it a copper wire, and lead- 
ing that through an electro-magnetic coil to the 
ground; and with that he held converse with the 
distant lightning, so far away that its voice could 
not be heard. If the gods of mythology, who 
hurl their thunderbolts, have a system in their 
signals, this apparatus would enable us to read 
their thoughts. Within a few months, a de- 
vice has been put into operation by which tele- 
graphic communication is kept up between the 
running cars on railroads and the stations, so 



MAGNETIC TELEGRAPH. 21 

that the positions of all the trains may at any 
time be known, and protection against collisions 
assured. To do this the metallic roof of the car 
is used as an inductive plate, just as was the house 
roof fifty years ago; and a wire passes from 
it through a signaling coil to the ground by way 
of the metal wheels and track. Near the roof 
outside, an electric wire is stretched on poles, 
through which electric flashes, like lightning, are 
sent, and they set up by induction in the roof 
electric currents similar to those passing over the 
wire, which are read as signals by the observer; 
and, conversely, signals are sent from the roof to 
the wire by induction coils in the car. The ex- 
perimental demonstration in Princeton has not been 
lost, though buried so long, and to-day it throws 
another safeguard around our lives. * 

The first electro-magnetic engine for generating 
power was made by Henry, at Albany, in 1831.f 
His clear mind was not deluded into the belief 
that such an apparatus could supersede the steam 
engine as an economical motor, and he warned the 
world against that delusion. Zinc, as fuel in a bat- 
tery, is more costly than coal in a furnace. Still, 
he saw and said that in exceptional cases it might 
be useful; a result now coming to pass, dependent, 
however, upon the discovery of magneto electricity 

* See Appendix, Note D. 
f See Appendix, Note E. 



PROFESSOR HENRY AND THE 



by which galvanic batteries are dispensed with, 
and electricity, made in quantities from some 
great and economical source of power, is distrib- 
uted to Henry's machines wherever they may be. 

In many volumes, some of which have perished 
by fire, and some remain, were laid out lines and 
plans of investigation by Professor Henry, needing 
only leisure and means for their development, 
covering fields where other investigators have 
since reaped rich harvests of fame, but from which 
he was debarred by the pressure of his other occu- 
pations here. In those records are contained the 
evidence that the great intellect, which did so much 
with so little, was capable of grasping the whole 
circle of physical science, and of enriching and 
adorning any department of it to which his efforts 
might be directed. 

But he was destined for another career. A be- 
nevolent Englishman, inspired by the noble ambi- 
tion to aid in elevating mankind, had bequeathed 
to the United States a great sum of money to be 
used for ' ' the increase and diffusion of knowledge 
among men." It was a splendid gift, and a sacred 
trust. Who was to be found equal to the task of 
effecting this grand purpose ? The civilized world 
was interested in that question. Mankind was the 
beneficiary of the trust; and all men were entitled 
to be considered in its administration. By the 
common consent of the wisest and best of Europe 



MAGNETIC TELEGRAPH. 23 

and America, Professor Henry of Princeton Col- 
lege was selected, and solicited to assume that 
onerous duty. What tribute was that to the 
achievements, the attainments, and the character 
of the man ! He must be famous, that his selec- 
tion might at once command the assent of the 
world ; he must be learned, that he might be able 
to carry out the purposes of the donor ; and he 
must be virtuous, that he should not degrade the 
high office to any base or selfish uses. And thus 
he was called. 

When brought to the parting of the roads, choice 
was extremely difficult. On the one hand, a life 
devoted to the most delightful of all pursuits — the 
searching out the laws of nature, which are the 
thoughts of God ; a reputation already great and 
daily growing ; and a happy home, surrounded by 
congenial and loving friends, and undisturbed by 
cares for the present or the future. On the other 
hand, an abandonment of the field of scientific 
research, where the harvest was abundant and the 
laborers few ; and a surrender to others of the 
prizes he saw glittering before him in the race 
he was running ; and furthermore, a grapple with 
the problems of organization and finance, and 
with the discordant elements which the scheme of 
the Smithsonian Institution would necessarily 
evoke. He foresaw that he might find himself, after 
some years had passed, like a giant shorn of his 



24: PROFESSOR HENRY AND THE 

strength; on the one side outrun in the race where 
he had ever been in the lead; and on the other so 
hampered and crippled as to be unable to accom- 
plish the great objects for which alone he was 
about to abandon his first love. That high sense 
of duty which governed him in every act of his 
life decided the question, notwithstanding his firm 
conviction that in accepting the trust he left the 
happiest days of his life in the past. 

Perhaps he might have decided otherwise if 
Princeton College had been then as it is now. Per- 
haps he then might have felt, that with such 
ample resources at his command as are now to 
be found here, his services to humanity might 
be greater as a soldier in the ranks than as a 
commander in the field. But at that time no one 
had arisen among the friends of this institution 
who, like the Medici of the fifteenth century, was 
able at the same time to gather the wealth of the 
world by the arts of honorable commerce, and to 
appreciate that the gathered wealth of the world 
owes its existence and preservation to science, to 
art, and to literature ; and that therefore it is due 
to education that it should be encouraged by 
noble gifts, such as have enlarged the ca- 
pacity of the College of New Jersey, and re- 
flected honor upon the names of those whose gen- 
erous hearts, guided by wisdom, have led them to 
broaden these ancient foundations, and to arm 



MAGNETIC TELEGRAPH. 25 

with improved facilities the workers who are here 
devoting their lives to the advancement of knowl- 
edge. All honor to such men." Had such assist- 
ance come earlier, the career of the great scientist 
might have been different ; but it was not to be, 
and thenceforth another life opened before him, 
and another man was unfolded to the world. 

Perhaps the highest praise that can be bestowed 
upon any man, is to say of him that he is just 
equal to all the duties ever imposed upon him, 
and never above them ; that his reserves are 
not called into action until the emergency re- 
quires them. Such men are the great benefactors 
of mankind. Such a man was the Secretary of the 
Smithsonian Institution. The principles he laid 
down for the administration of the noble gift of 
Smithson required time for their development, 
and promised no present brilliant results. The 
foundations were to be laid deep in the earth, 
where the laborer and his work were scarcely 
to be seen by the passer-by. No popular ap- 
plause would greet the achievement for years 
to come, while popular clamor was ever 
ready to cry out against the waste of time and 
money that produced no instant fruits. The 
man of clear purpose and resolute will stood guard 
over the work; and with just force enough, and 
no more, drove off the assailants till the foundations 

* See Appendix, Note F. 



26 PROFESSOR HENRY AND THE 

were all secure, the superstructure begun, and it 
was strong enough to stand alone. 

With the skill that would have adorned a pro- 
fessional diplomatist, he temporized and compro- 
mised, when he could no longer contend with suc- 
cess ; with the dash that would have illustrated 
a general, he attacked when the moment was pro- 
pitious, and the adversary off his guard. With 
the earnestness of sincere conviction, and the 
directness of demonstration with which his scien- 
tific training had armed him, he convinced, one 
by one, those who opposed his views, until at last 
the Kegents of the Institution, and Congress, sur- 
rendered their judgments to his, and the field was 
won. 

A great library was the dream of Mr. Choate, the 
most scholarly and persuasive of advocates; and, 
as a regent, he possessed and wielded a formidable 
power. It was hard to persuade him that a li- 
brary does not "increase knowledge among 
men," and that it is very likely to "diffuse" igno- 
rance. To discover and accumulate new truths, 
and to diffuse them over the whole earth, was the 
Secretary's conception of the donor's intention; to 
pile up in Washington a miscellaneous collec- 
tion in print of old truths and old errors, was the 
idea of the scholars; and they were so strong that 
a temporary compromise was necessary. The 
vigorous growth of the true conception at last 



MAGNETIC TELEGRAPH. 27 

overshadowed the false one, and the library no 
longer saps the life of the Institution. Professor 
Henry always thought that over every library 
portal should be written some such warning as — 
" Cave Canem " — beware of the lies. 

It was not till 1S52 that the serious attacks upon 
the Smithsonian came to an end. On the 24th 
of June, of that year, a United States Agricul- 
tural Convention met in the theatre of the 
Smithsonian building. The plan to plunder the 
Institution seems to have been carefully considered 
and matured ; and the officers of the Smithsonian 
were elected members of the convention. Stephen 
A. Douglas was at that time at the height 
of his power. He had risen from the ranks by 
the arts of the politician, and was the most influen- 
tial man in the Democratic party of that day. 
Although not yet forty years old, he had just 
succeeded in defeating General Cass in a contest 
for the presidential nomination at Baltimore ; and 
although he failed by a few votes to secure it, he 
had thrown it to Franklin Pierce, of New Hamp- 
shire, and thus kept it open for himself in 1856, 
as the Western candidate of the party. 

He was styled the " Little Giant " — not in deris- 
ion, but in admiration; as expressing the combi- 
nation of a small stature and great intellect. 
Eepresenting in the convention what was then 
an almost entirely agricultural constituency, he 



PROFESSOR HENRY AND THE 



thought that votes were to be got, and his influence 
strengthened, if he could bring home to them the 
spoils of the Smithsonian; and accordingly a reso- 
lution was introduced petitioning Congress to 
appropriate a portion of the Smithsonian money 
for an agricultural bureau ; and Judge Douglas 
undertook the congenial task of accomplishing 
the raid. The recollections of that battle are 
among the valued treasures of memory, asso- 
ciated in my mind with Joseph Henry. In such 
an assemblage, and with such a cause, Douglas 
was an adversary to be feared by any man. 
That he was an accomplished politician was 
proved by his great success ; and he was there 
to fix another step in the ladder by which he had 
climbed so high. His speech was adroit, as only 
he could make it. Its argument was founded upon 
the proposition that civilized man depends upon 
agriculture, without which barbarism would sweep 
over the land; and his conclusion was that the 
farmer was entitled to whatever assistance could be 
got out of the money of Smithson, whose benevo- 
lence could best be applied in encouraging those 
who were at the very foundations of civilization. 
It would be great injustice to Judge Douglas to 
assume that he supposed the diffusion of papers of 
turnip seed among farmers was that sort of " in- 
' ' crease and diffusion of knowledge among men " 
designed by Mr. Smithson ; but no doubt it would 



MAGNETIC TELEGRAPH. 29 

be an increase and diffusion of the knowledge that 
he was the friend of the farmer, and that was 
of more importance to him. The Secretary, sur- 
rounded by a few earnest friends, and prepared 
for the assault, sat in the back seat of the 
theatre quite unnoticed, kindling with righteous 
indignation at this nefarious plot to confiscate 
the funds of which he was the chosen guardian, 
and to destroy the institution devised by his intel- 
lect, reared by his unceasing efforts, and guarded 
so far by his sleepless vigilance. 

When the popular applause following the 
" Little Giant's " popular speech had subsided, 
the Secretary arose. In measured and digni- 
fied words he presented himself as the guard- 
ian of that fund, bound, so far as in him lay, 
to defend it from spoliation. He first developed 
the moral aspects of the question, and appealed, 
over the head of the advocate, to the honesty 
of the constituents he represented ; expressing the 
most generous confidence that the farmers of this 
country would never consciously be parties in an 
attempt to seize that which belonged to mankind 
in general, or seek by a forcible partition to destroy 
the unity and efficiency of the fund. 

The legal aspect of the question he next dis- 
cussed like an equity lawyer ; and denounced in 
scornful sentences that attempted breach of trust 
which was implied in the resolution. 



30 PROFESSOR HENRY AND THE 

And then, out of the fullness of his knowledge, 
with abundance of illustration and example, he 
demonstrated that the discovery of new truths, 
and their application to the arts, had elevated the 
farmers from the mere drudges they were in the 
seventeenth century to their present high state of 
intelligence and comfort. 

The effect was overwhelming ; and the " Little 
Giant " must have felt that there was another 
"giant" there to whose title no diminutive prefix 
could be properly applied. 

The meeting adjourned till the next day, and 
these significant words were written in the Secre- 
tary's diary, under date of June 25 : " Judge 
" Douglas, toward the close, made an apology for 
" the warmth of his expressions. I did the same. 
" Judge Busk followed — so the whole was am- 
" icably settled." 

Since that day no further assaults have been 
made on the Smithsonian Institution; and it 
stands a proud monument to the genius, the 
learning, the labor, and the character of the great 
Secretary; who was content to sink his personality 
in the impersonal institution — to be overshadowed 
by the creature of his own creation, in order that 
true knowledge might the better be increased and 
diffused among men. 

The conscientious obligation he felt pressing 
upon him to lose no opportunity for diffusing 



MAGNETIC TELEGRAPH. 31 

knowledge and correcting error, imposed a vast 
amount of unrecognized and unrequited labor. 
The intellectually halt, and lame, and blind, con- 
tinually resorted to him for help, either in person 
or by letter ; and they never were sent away 
empty. Like the home of the lovely country parson 
in the Deserted Village, 

" His house was known to all the vagrant train ; 
He chid their wanderings, but reliev'd their pain." 

They who have witnessed some of those deeds 
of charity, will never forget the gentle patience 
with which he listened to the beggars for knowl- 
edge, and the simple way in which he conveyed to 
their imperfect intelligences the truths they were 
seeking. Their self-conceit was often offensive ; 
but he knew it was the product of ignorance, and 
his effort was to cure the disorder. He was no 
more repelled by the disagreeable symptoms, than 
the physician is who must treat a loathsome disease. 
On one occasion, in my presence, one of these crip- 
ples refused to accept the instructions of the great 
physicist, on a very simple question of dynamics, 
applicable to a project he had in hand; but instead of 
dismissing him, the master quietly took down "Hut- 
ton" from the book-case, and patiently read that 
author's confirmation of the law he had been teach- 
ing. What an exhibition of true humility ! Per- 
haps, thought he, "I can give a new direction to this 



32 PROFESSOR HENRY AND THE 

" man's mind, who may yet do something useful ; 
" and what matters it that he scorns me." 

No one can form an adequate estimate of the vast- 
ness of his mind, of the extent and accuracy of his 
learning, and of his power to discern the correla- 
tions of knowledge, who has not carefully read 
the instructions mapped out by him for the guid- 
ance of investigators working under the auspices 
of the Smithsonian Institution. They constitute a 
set of charts, which, for years to come, will guide 
the explorer safely and surely in future voyages 
for the discovery of new truths ; and are a monu- 
ment, attesting the fidelity with which the great 
trust was executed, and vindicating the sagacity of 
those eminent men, who, in 1846, saw, what his 
innate modesty forbade him to see, that Joseph 
Henry was, of all living men, the most fit to ad- 
minister a fund whose object was "the increase 
"and diffusion of knowledge among men." 

Passing by thus hastily the great achievements 
illustrating the long and happy life of Henry, 
let us examine with more particularity his connec- 
tion with the electro-magnetic telegraph; whose 
creation has so largely modified the course of mod- 
ern civilization, and endowed the dull earth with 
nerves, like those of the living frame, whereby the 
whole body of mankind instantly feels the joys or 
sorrows of any of its members. 

How to communicate intelligence instantly, over 



MAGNETIC TELEGRAPH. 33 

distances so great that the voice cannot be heard, 
had been well known to organized societies from 
remote antiquity. Visible signals, made by mov- 
ing vanes by day, and lighted torches by night, 
were known to Greeks and Romans alike; and 
more recently the alphabet was associated with 
these movements, so that alphabetical messages 
were freely communicated. 

Even barbarous nations and tribes possessed this 
art in a high degree of perfection; and the arrival 
and progress of Cortes in Mexico were communi- 
cated by telegraphic signals, corresponding with 
the sign language of the Aztecs, to the capital of 
the doomed Montezuma. 

When atmospheric electricity came to be artifi- 
cially generated, it occurred at once to ingenious 
men that it might be used for telegraphy; and, in 
1774, the first electric telegraph ever constructed 
was established at Geneva by Lesage. He used 
twenty- four wires, each connected with an electro- 
scope, whose function it is to move when the wire 
is charged with electricity, and by means of 
which any of the letters of the alphabet could 
be transmitted, by simply discharging a prime 
conductor of an electrical machine into the 
wire corresponding to that letter. This com- 
plicated apparatus was subsequently improved 
by using only one wire, and causing lettered 
wheels to revolve synchronously at the two sta- 



34 PROFESSOR HENRY AND THE 

tions, so that the same letter would appear at 
the same time to both operators. By this appara- 
tus, whose principle of synchronous revolution is 
the same as that now used in the printing tele- 
graph, the sender would simply close the circuit 
on his electrical machine when his revolving 
wheel presented the desired letter, and the pith-ball 
electroscope, moving at the receiving end at the 
same instant, would indicate to the receiver that 
the letter then presenting itself to him on his 
wheel was the one intended. 

A number of other inventors used static elec- 
tricity for the same purpose during the latter years 
of the last century, and the earlier ones of this. 
In England, Eonalds had a line of eight miles 
on which the wire was suspended from poles, 
and insulated by silken strings;* and in 1796, 
Salva, in Spain, worked a line by static electricity 
twenty-six miles long.f 

In the year 1800 Volta produced the voltaic pile, 
and gave to the world that new manifestation of 
electricity called galvanism. In that form this 
subtle agent is far more manageable than in 
the form of static electricity; and by the use of 
galvanic batteries a current of low tension, but 
of enormously greater power, can be maintained 
with little difficulty; whereas static electricity 

* See Appendix, Note G. 
f See Appendix, Note H. 



MAGNETIC TELEGRAPH. 35 

is like lightning, and readily leaps and escapes 
from the surfaces on which it is confined. The 
galvanic current also readily decomposes acid- 
ulated water, and many other substances, and 
this capacity was soon applied to the purposes of 
telegraphy. Scemering, in 1807, invented a tele- 
graph on this plan, and continued it for several 
years in Munich, publishing accounts of it in sci- 
entific journals, and exhibiting it to learned socie- 
ties.* Others followed his lead, until finally it 
came into commercial use in England in 1846 as a 
rival to the electro-magnetic telegraph of later 
invention ; but requiring its aid, as an alarm. f 

In 1*820, Oersted discovered the capital fact that 
a galvanic current, passing through a wire placed 
horizontally above, and parallel to, an ordinary 
compass needle, will cause that needle to sway on 
its axis to the east or west, according to the direc- 
tion of the current through the wire. At once 
Ampere suggested the application of the new dis- 
covery to the old telegraph, whereby galvanism 
might be substituted for static electricity, and 
the deflection of a magnetic needle for the diver- 
gence of the pith balls of the electroscope. Baron 
Schilling, a Russian nobleman, inspired by the love 
of science, accordingly took up this suggestion, 
and constructed a galvanometer or needle tele- 

* See Appendix, Note I. 
t See Appendix, Note K. 



36 PROFESSOR HENRY AND THE 

graph, which in a practical and operative form 
was exhibited to the Emperor Alexander in 1824, 
and came to be well known to scientific persons 
at that time.* 

In 1833, Gauss and Weber set up a single circuit 
galvanometer telegraph on this plan at Gottengen, 
leading the wire over the house-tops, on insula- 
tors, as we do now; and by the deflections of the 
needle to the right and left made up the alphabet, 
as it had been done before when using other means 
for moving the vanes, f 

Their apparatus, however, is perfectly silent. 
The needle is suspended by a thread when the noise- 
less current sways it to and fro with but feeble 
force; and it is incapable of calling the attention of 
the operator to receive its message. These were 
serious difficulties, to be overcome by other princi- 
ples, and other inventions, which would supersede 
this one. 

Following Oersted, Arago, in France, in 1820, 
made the next capital discovery. It was but 
a little thing he saw — simply that a sewing needle, 
surrounded by a coil of wire, through which a vol- 
taic current passed, had become magnetic; but that 
little thing has grown to be mighty. This obser- 
vation was the complete discovery of electro-mag- 
netism, which had been dimly seen in Oersted's gal- 

* See Appendix, Note L. 
f See Appendix, Note M. 



MAGNETIC TELEGRAPH. 37 

variometer; and was the germ of the electro-mag- 
net. For four years this beautiful discovery was 
experimented with by all the scientists in Europe 
before another step was taken; and then William 
Sturgeon, of England, produced the electro-magnet. 
It consisted of a large soft iron wire, bent into 
a horse-shoe form, coated with varnish, and 
wrapped with a spiral coil of naked copper wire 
from end to end, through which the voltaic cur- 
rent might be passed. This bent wire became a 
magnet while the current flowed, but lost its mag- 
netism when the current ceased. 

Here then was born into the world an apparatus 
capable of exerting a stronger power at the will of 
the operator, by merely opening and closing the 
voltaic circuit; and it was then thought that the 
difficulties in the way of the telegraph were con- 
quered. The experiment was soon tried with 
Sturgeon's magnet by Barlow, an eminent scien- 
tist ; and in January, 1825, he published his results 
in the "Edinburgh Philosophical Journal" in 
these words: 

" The details of this contrivance" (a telegraph) 
" are so obvious, and the principle on which it is 
" founded so well understood, that there was only 
" one question which could render the result 
" doubtful; and this was, is there any diminu- 
" Hon of effect by lengthening the conducting 



38 PROFESSOR HENRY AND THE 



"wire?" If not, he proceeds to say: "Then no 
" question could be entertained of the practicabil- 
" ity and utility of the suggestion above adverted 
"to. I was, therefore, induced to make the 
" trial; but I found such a sensible diminution 
" with only two hundred feet of wire, as at once 
" to convince me of the impracticability of the 
" scheme." 



Barlow's experiment was repeated by other scien- 
tists in that and following years with a like result; 
until it came to be accepted in the scientific world 
that the telegraph could not be worked with the 
newly- discovered electro-magnetism. So strongly 
was this fixed in the opinion of the day, that as 
late as 1837 — thirteen years after the invention of 
the electro-magnet by Sturgeon — so eminent a sci- 
entist and discoverer as Wheatstone, pronounced 
the electro- magnetic telegraph impossible, on an 
occasion when the very question was submitted to 
him for decision by Cooke, at the suggestion of 
Faraday himself. This fact is so important, and 
so conclusive on the question now under examina- 
tion, that I read Wheatstone's own account of it, 
submitted by himself to arbitrators who were to 
decide a controversy between himself and Cooke 
as to their respective merits as inventors of 
one form of the electro- magnetic telegraph. He 
says: "I believe, but am not quite sure, that 



MAGNETIC TELEGRAPH. 39 

1 it was on the first of March, 1837, that Mr. 
' Cooke introduced himself to me. He told me 
' he had applied to Dr. Faraday,* and Dr. Roget, 
* for some information relative to a subject on 
' which he was engaged, and they had referred 
1 him to me as having the means of answering 
' his inquiries. Eelying upon my 

1 former experience, I at once told Mr. Cooke that 
1 it ivould not, and could not, act as a telegraph, 
1 because sufficient attractive power could not be 
' imparted to an electro -magnet interposed in a 
1 long circuit ; and to convince him of the truth of 
' this assertion I invited him to King's College to 
1 see the repetition of the experiments on which 
' my conclusion was founded. He came, and 
1 after seeing a variety of voltaic magnets which, 
{ even with powerful batteries, exhibited but slight 
' adhesive attraction, he expressed his disap- 
t pointment."\ 

Cooke confirms this statement by saying: " It 
1 was my inability to make the electro-magnet act 
' at long distances which first led me to Mr. 

' Wheatstone."t 

Let the difficulty of making the discovery 
which overcame this impossibility be judged by 
the fact, that for so many years, such men as 
these were unable to do it when it was needed; 

* See Appendix, Note N. f See Appendix, Note 0. 

X See Appendix, Note P. 



40 PROFESSOR HENRY AND THE 

and let that fact answer the envious suggestion 
that Henry's achievement involved no great 
amount of analytic and inventive power. 

"When Barlow's demonstration was published in 
1824, Henry had never seen an electro-magnet, nor 
tried an experiment in electricity. When, how- 
ever, two years later he took up the subject, and 
began the first set of regular scientific investiga- 
tions ever attempted in the United States, he de- 
duced from Ampere's law the principle that the 
voltaic currents, carried on wires around the iron 
core of the electro-magnet, should move in planes 
at right angles to the axis of that core — which 
they could not do even approximately if the core 
itself were insulated, as in Sturgeon's small 
magnet, having only one coil of naked wire 
wound spirally around it, necessarily leaving open 
spaces between the successive spirals, and so lead- 
ing the current like a cork screw around the core. 
He also reasoned that, as the current must be led 
through a spiral circuit, which theoretically should 
be circular, the departure from its true course 
might be counteracted by winding the wire on a 
second spiral outside of the first, but with its 
spiral angle opposed, so that the resultant of the 
current from the two spirals would be the same as 
if it revolved in planes at right angles to the axis 
of the core. 

He brought his reasoning to the test of experi- 



MAGNETIC TELEGRAPH. 41 

ment. Instead of insulating the core, he wrapped 
a fine copper wire with silk, and wound it on the 
core; each spiral closely packed against its fellows, 
so as to correct the spiral error as much as possible 
in each layer; and then he wound the wire in a 
second spiral over the first, but with the pitch of 
the screw, so to speak, in the opposite direction. 
And carrying out the principle he multiplied the 
coils to an enormous extent in the same way. The 
result justified and established his theory; and his 
magnets at once showed a capacity hundreds of 
times greater than any then known to science.* 

But this was not all. Another step had to be 
taken before Barlow's demonstration could be over- 
thrown, and the telegraph made possible. And 
this he took by discovering and establishing the 
fact, that a magnet with a long fine wire coil must 
be worked by a battery of " intensity," composed 
of a large number of cells in series, when a distant 
effect was required; and that the greatest dynamic 
effect, close at hand, is produced by a battery of a 
very few cells of large surface, combined with a coil 
or coils of short coarse wire around the magnet. 

These discoveries and inventions solved the 
problem which had seemed to European scientists 
insoluble; and in one account of them which was 
published in " Silliman's Journal" for January, 
1831, he says : " The fact that the magnetic action 

* See Appendix, Note Q. 



42 PROFESSOR HENRY AND THE 

" of a current from a trough is at least not sensibly 
" diminished by passing through a long wire, is 
" directly applicable to Mr. Barlow's project of 
"forming an electro-magnetic telegraph."* This 
reference was to Barlow's paper of 1824, in 
which he had demonstrated the impracticability 
of the telegraph. 

Had these things been done in the Eoyal Institu- 
tion, and read before the Eoyal Society, Wheatstone 
would not have been found, in 1837, denying the 
possibility of an electro-magnetic telegraph ; and 
Faraday would have been able to answer Cooke's 
question, without sending him to Wheatstone for 
the information. In those days, however, the 
United States were held in no higher estimation in 
Europe, than Nazareth was in former days in 
Jerusalem ; and no one in England read an 
American book. 

But not content with having reasoned out, and 
demonstrated, that distance was no longer the sole 
impediment in the way of the magnetic telegraph, 
Henry, in 1831, established the first electro- 
magnetic telegraph that ever existed. In the 
Albany academy he strung a mile of line wire, 
and with an " intensity battery " at one end, and his 
spool of long fine wire at the other, he operated the 
armature of the first sounding telegraph of any 
kind. When the armature was attracted by 

* See Appendix, Note R. 



MAGNETIC TELEGRAPH. 43 

the magnet, it struck a small bell or sounder, 
which spoke its signals ; and that apparatus there 
was maintained to illustrate the telegraph to the 
students. 

When applied to practical use, some code of 
signals must be arranged for translating the 
successive taps of the armature ; but that was 
well known in the telegraphic art for ages, 
needing only good judgment in arranging it, 
so that the letters which occur most frequently, 
shall be represented by the smallest number of 
motions ; just as Gauss and Weber arranged their 
needle -telegraph code in 1833, when the movements 
of their needle to and fro, in a number of simple 
combinations, indicated the alphabet.* 

These " spools" of Henry have been the means 
by which most of the great discoveries in electro- 
magnetism have since been made. Faraday and 
Henry used them in their famous researches already 
referred to, in which they discovered magneto- 
electricity. Sturgeon, in writing of them, says : 
" Professor Henry has been enabled to produce a 
" magnetic force which totally eclipses every other 
" in the whole annals of magnetism; and no parallel 
" is to be found since the miraculous suspension of 
" the celebrated oriental impostor in his iron 
" coffin, "f Without them we could not have the 

* See Appendix, Note S. 
\ See Appendix, Note T. 



44 PROFESSOR HENRY AND THE 

telegraph, or the still more marvelous telephone. 
They are to-day essentials of modern living ; and 
are as familiar to us as spools of cotton. Judg- 
ing by their results, they constitute the most im- 
portant discovery which has ever been made in 
electricity since Volt a created the battery. 

Henry also put in operation at Princeton in 1835 
the very simple and obvious plan of using the "in- 
4 ' tensity spool and battery," working through long 
distances, to open and close the circuit of a "quan- 
" tity spool and battery," stationed where the work 
was to be done; thus making the powerful mag- 
net, at short range, the servant of the weak one at 
long range. In this state he left the problem 
entirely solved, to those who could procure the 
money to practically apply his discoveries to the 
commercial uses of man. 

That task was no easy one. In 1831 there were 
no railroads and no steamships. Over rough 
country roads the mails were carried in wagons or 
coaches, and the postage on a single letter was a 
shilling for short distances, and twice as much for 
longer. But little capital had accumulated in this 
country; and corporations, those powerful instru- 
ments for uniting the slender means of the many 
into a compact force for the development of great 
industrial enterprises, were hardly known. If the 
most perfect telegraph apparatus of to-day had 
been then presented to the public, no company 



MAGNETIC TELEGRAPH. 45 

could have been formed to exploit it. The time had 
not yet come; nor could it come until railroads were 
built, and the exchange of material things had 
been rendered easy. 

In Europe, where money and railroads were more 
abundant, the telegraph was first put into practical 
use. Wheatstone and Cooke, in England, in 1838, 
having first, however, seen and talked with Henry 
on the subject in 1837,* after they had first de- 
cided the thing to be impossible, established a 
practical commercial telegraph line between Pad- 
dington and West Dayton, a distance of thirteen 
miles ; and a shorter line was in Munich.f In 
this country private capital could not be raised 
for the purpose at all ; not because there was 
any doubt that the thing could work, but because 
no one supposed it would repay the investment ; 
as it certainly would not have done in those early 
days. At last Congress was induced to do what 
private enterprise refused, and in 1S44, six years 
after the English lines had been in practical oper- 
ation, and seven years after the Bavarian, money 
was appropriated for the line between Baltimore 
and Washington. This was accomplished, after 
great exertions, by persons hoping for the reward 
which a patent for some of the contrivances con- 
nected with that particular plan promised. 

* See Appendix, Note U. 
f See Appendix, Note V. 



46 PROFESSOR HENRY AND THE 

Neither in England, where Wheatstone had a 
patent founded on Henry's inventions, nor here, 
where Morse had a similar one, could the telegraph 
have been introduced for years after it really 
was, but for the beneficient operation of the patent 
laws. But few men are to be found who will 
incur the risks, and expend the money, incident 
to the introduction of a new and untried industry, 
without the hope of that pecuniary return, which in 
such cases, can only be secured by the exclusive 
use for a " limited time" of the new thing, during 
which it is hoped the original losses may be repaid, 
and a profit earned.* 

Let us now consider what would have been the 
position of Henry in the world, if at any time 
before his inventions had been so long in public 
use that he had lost his rights, he had taken a 
patent for. 

First, his magnetic spools, pure and simple; 

Secondly, the combination of a magnetic spool 
of long fine wire, with an " intensity battery," for 
the purpose of producing a practical magnetic 
effect at great distances; 

Thirdly, the combination with such an appa- 
ratus of a quantity battery, operating upon a spool- 
magnet of coarse and short wire, at a distance 
from the intensity battery; whereby the great lift- 

* See Appendix, Note W. 



MAGNETIC TELEGRAPH. 47 

ing power of the quantity magnet might be con- 
trolled by the intensity combination; 

And finally, the combination of the intensity 
battery and spool, with a vibrating armature, so 
arranged as to strike a sounder when the circuit 
is closed or opened at the sending end, for the 
purpose of transmitting intelligible messages tele- 
graphically. 

All these he might have patented in the United 
States at any time during several years after his 
discoveries and inventions were made; and he 
could have held them against the world. That he 
was the first man to do all these things is not in 
doubt anywhere. If he had taken such a patent, 
as late as 1837, he would have controlled the 
telegraph in this country, certainly until 1851; 
and unless he had then been adequately rewarded 
for his great inventions, his term would have been 
extended till 1858. Imagine the good he would 
have done to science had the wealth which this 
would have produced been poured into his purse ! 

But listen to his noble words: " At the time of 
" making my original experiments in electro- 
" magnetism in Albany, I was urged by a friend 
" to take out a patent, both for its application to 
" machinery, and to the telegraph; but this I de- 
" clined, on the ground that I did not then consider 
" it compatible with the dignity of science to confine 



48 PROFESSOR HENRY AND THE 

" the benefits which might be derived from it to the 
if exclusive use of any individual." 

Pure science was his beloved, and he could not 
make merchandise of her. 

When that sentence was written, other eminent 
scientists had thought differently of this question, 
and had patented their discoveries ; and lest he 
might seem to cast a reproach upon them, and to 
say "lam holier than thou," his humble spirit 
added these words: "In this, perhaps, I was too 
fastidious." 

It must have occurred to him at times, when he 
needed money for his experiments, and when he 
saw the fruits of his labor enriching the w r orld, 
that he might have taken some share of the 
wealth; but he would not taint with selfishness his 
generous gift. How valuable in money it was he 
knew full well. Even for that fragment of it," 
then for six years by him given to the public, 
which was carried to Morse in 18 37 to enable 
him to construct his special plan of a recording 
telegraph in that year, now practically obsolete, 
Dr. Gale, who carried it, received a share in 
the patent which was founded upon it, and 
without which it could not have existed. For 
that share fifteen thousand dollars in cash were 
subsequently paid to him. And its use for the 
telegraph was but a small part of its infinite va- 



MAGNETIC TELEGRAPH. 49 

riety of applications to the arts, and the purposes 
of man. 

Come with me now into a telegraph office, and 
let us see what we find there. If the line be a 
short one — say thirty or forty miles — you will see 
but one of Henry's spools, fixed to a table, 
having a piece of iron called an ''armature," 
capable of vibrating in front of its poles, and so 
arranged that when the "spool-magnet*' attracts 
it, it will vibrate and strike a sounding-bar of 
sonorous metal, which gives out distinctly the 
sound of the tap. The "spool" is wound spirally 
in layers with several hundred feet of fine copper 
wire, covered with silk, in the manner specified 
by Henry in " Silliman's Journal." At the 
other end of the line is a battery, composed of a 
number of cells in series, called by Henry for 
distinction an "intensity battery; " and the wire 
circuit is supplied with a simple device, so that it 
may be opened or closed by the operator's finger. 
When he closes it, a current of electricity 
flows from the "intensity battery" along the 
wire, and around the coil of the "intensity mag- 
net," and the armature strikes the sounder and 
gives the signal. The listener hears it; and as the 
order of the taps progresses in accordance with 
a pre-arranged artificial code, to express the let- 
ters of the alphabet by combinations of succes- 
sive taps — just as the old visible signals were ar- 



50 PROFESSOR HENRY AND THE 

ranged by combinations of the successive move- 
ments of the vanes, or afterwards of the needle of 
the Gauss and Weber telegraph— he hears letter 
after letter tapped out, and the message is under- 
stood. 

Now, that apparatus has nothing about it 
more than was in Henry's Albany telegraph of 
1831; nor could it operate if it omitted any one of 
the inventions, either singly or together, which 
were then for the first time combined. It depends 
entirely upon the discoveries made by Henry before 
1831; and it could not have existed in the world 
earlier than those discoveries, by the use of any 
means then known to man ; nor since by any 
other means than those discovered by Henry. 

Henry used a bell as a sounder; they now use 
a metal bar and a sounding box. Henry reversed 
the battery current, whereby no spring is needed 
to withdraw the armature for the purpose of 
vibrating it; and that is the common practice in 
English and German telegraphs. Here they 
generally merely interrupt the circuit, and the 
armature is withdrawn from the magnet by a 
spring; although Henry's device is also used here 
largely, and is essential to the quadruplex instru- 
ments.* 

If, however, the telegraph line is a long one — it 
may be a thousand miles or more — then you will 

* See Appendix, Note X. 



MAGNETIC TELEGRAPH. 51 

see two sets of Henry's spools, and two batteries. 
One is the "intensity battery and spool" first de- 
scribed; and the coil of fine wire maybe, and often 
is, several thousand feet long— while the battery 
is composed of more than a hundred cells. The 
distance being so great they do not attempt to 
send force enough through the intensity circuit to 
operate a sounder, but only to open and close the 
local circuit of Henry's quantity battery and 
spool. That circuit consists of a battery of but 
one or two cells of large surface, and a spool 
with about a hundred feet of coarse wire wound 
around its core. The intensity combination opens 
and closes this quantity circuit, whose armature 
strikes the sounder, just as the intensity armature 
itself does on shorter lines. This obvious plan 
Henry described and exhibited in Princeton to his 
classes, long before any magnetic telegraph was 
ever commercially constructed, or the convenience 
of such an arrangement had resulted from the 
great length to which the lines are stretched. 

Upon that apparatus there are but four names 
to be written. Oersted, who discovered the effect 
of the voltaic current upon the magnetic needle ; 
Arago, who discovered that the voltaic current 
could generate magnetism; Sturgeon, who produced 
the first electro-magnet; and Henry, who discovered 
the conditions under which an electro-magnet 
might be operated at a distance — who invented the 



52 PROFESSOR HENRY AND THE 

devices by which it could so operate — and who 
applied those devices to an operative telegraph, of 
the same form and substance as that now in use 
all over the world. Beyond their discoveries and 
inventions nothing is essential to the present tele- 
graph, except that which was of common knowl- 
edge when those discoveries were completed, and 
that ordinary mechanical skill which is far below 
the level either of discovery or invention. 
This is the record, and so it will stand forever. 

•' The moving finger writes ; and having writ, 
" Moves on : nor all your piety nor wit 
" Shall lure it back to cancel half a line, 
" Nor all your tears wash out one word of it." 

Forty years had fled away since as teacher and 
pupil we first met, and they seemed like a dream 
that is past, when again we met to part forever 
in this world. In the chamber where the 
angel of death hovered over him, just ready to 
call him away, he talked thankfully of the past, 
and hopefully of that eternity on whose verge he 
stood. The vigor of youth and of manhood had 
been all spent in the service of humanity, and his 
strength was gone. The pallor of disease had 
dispelled the delicate hues of health, and time had 
traced its furrows on his brow. But the unclouded 
intellect still held its sway, enthroned in that 
magnificent head on which the snows of many 
winters had drifted ; and the gentle loving spirit 



MAGNETIC TELEGRAPH. 53 



still, as of old, illumined his beautiful face, but 
with a clearer, warmer light, reflecting the heaven 
upon which he gazed. For himself he had but 
one regret — that he had not been spared to 
complete his last great labor, by which he 
hoped to confer still one more benefit upon hu- 
manity, by discovering some means affording 
greater security for mariners on the treacherous 
coast, when fogs draw down their impenetrable 
veils over the lights, and the syren's voice fails to 
pierce the fickle air. 

The faithful servant — faithful unto death — only 
mourned that he could not have done more. With 
the humble spirit of the true Christian, after hav- 
ing in the estimation of his fellow- men done so 
much, he, knowing better than others how much 
was yet to be done, exclaimed "I am an un- 
profitable servant. " 

Such a life and such a death exalt and glorify 
humanity; illustrating and indelibly impressing 
upon our hearts the sublime truth, that man is 
made in the image of God. 

" Along the smooth and slender wires, the sleepless heralds run, 
" Fast as the clear and living rays go streaming from the sun; 
11 No peals or flashes, heard or seen, their wondrous flight betray, 
" And yet their words are quickly felt, in cities far away. 

" Nor summer's heat, nor winter's cold, can check their rapid course ; 
4t Unmoved they meet the fierce wind's blast, the rough waves 
sweeping force. 



54 PROFESSOR HENRY. 

" In the long night of rain and wrath, as in the blaze of day, 
• ' They rush with news of weal or woe to thousands far away. 

" But faster still than tidings borne on that electric cord, 

" Rise the pure thoughts of him who loves the Christian's life and 

Lord, 
" Of him who taught, in smiles and tears, with fervent lips to pray, 
" Maintains high converse, here on earth, with bright worlds far 

away. 

1 ' Aye, though no outward wish is breathed, nor outward answer 

given, 
' ' The sighing of that humble heart, is known and felt in heaven ; 
" Those long frail wires may bend or break, those viewless heralds 

stay; 
" But faith's last word shall reach the throne of God, though far 

away.* 



See Appendix, Note Y. 



^iPiPiEiisnDizx: 



Note A, Page 11. 
Life of Faraday, by Bence Jones. London 



Vol. II. , p285. 



Note B, Page 12. 



Faraday's Experimental Researches. Vol. I. , p. 
1, and plate. 

Note C, Page 12. 

A full account of this is in Bence Jones' Life of 
Faraday, Vol. II., p. 1 to 6. Faraday tried it in 
1824, '25, and '28, and failed each time; although, 
since magnetism had been developed from electric- 
ity, the converse of the problem seemed very 
feasible. On the 21st of September, 1S31, he tried 
the experiment with an iron ring electro -magnet, 
constructed according to Henry's invention, using 
an intensity battery of ten pairs. One-half of the 
ring was wound with 72 feet of insulated wire; and 
the other half with about 60 feet, in the circuit of 
which a galvanometer was placed. When the 
battery was closed upon the first circuit, the iron 
ring became magnetic, and a current of electricity 
was set up, by induction, in the second circuit, 



56 APPENDIX. 



and the galvanometer moved. This experiment 
says his biographer, is " the discovery by which 
he will be forever known. " 

Henry's account of his own discovery exhibits 
the very same apparatus. He used his electro- 
magnet, capable of lifting 600 or 700 lbs., and 
united its poles by an iron bar or " keeper," firmly 
fixed, so as to form a complete circuit — the same 
as the iron ring in Faraday's experiment. Around 
this " keeper" he wound about 30 feet of insulated 
wire, in many layers, occupying about one inch in 
the length of the keeper, and placed a galvanom- 
eter in the circuit of the coil. When the battery 
circuit was closed and broken on the coil of the 
magnet, the galvanometer moved, and the great 
discovery was made {Sillimari's Journal, July, 
1832). 

Faraday had been working over it for seven 
years. Henry never touched the question till 1827. 

Note D, Page 21. 

In another arrangement of this same invention, 
a heavy wire is laid between the tracks, and large 
inductive coils, near the floor of the car, are 
affected by the current in the line wire. Henry 
exhibited the principle of this apparatus in 
Princeton, when in the cellar of the Philosophical 
Hall, induced currents were set up in a wire lead- 
ing around the apartment, induced by passing a 
battery current through a similar wire in the 
upper story, thirty feet above, and with two floors 
between. 



APPENDIX. • 57 



Note E, Page 21. 

This engine is now at Princeton in the labora- 
tory. 

Note F, Page 25. 

Since the accession of President McCosh, the 
donations to Princeton College have been munifi- 
cent. John C. Green, Esq., of New York, in his 
lifetime, and the trustees of his estate since his 
death, have given princely gifts, amounting to 
millions. The Green School of Science, with its 
splendid buildings and complete apparatus, sup- 
ported by an endowment for its professors; the 
beautiful library, with an ample fund; Dickenson 
Hall, containing elegant lecture and class- rooms; 
Witherspoon Hall, one of the noblest structures 
in the State, and Edwards' Hall— both dormitories 
for students; and large sums for general purposes, 
are the permanent monuments of this generosity. 

Henry G. Marquand, Esq., of New York, has 
erected a beautiful chapel, bearing his name, un- 
surpassed by any college chapel in this country; 
and in addition, has endowed a professorship of art. 

Messrs. Eobert L. Stewart and Alexander 
Stewart, brothers, gave to the College during 
their lifetime the splendid Potter mansion, as a 
residence for the President. 

Mrs. Robert L. Stewart, of New York, has 
founded the School of Philosophy, and lately has 
given $150,000 to establish the chairs in this school 
— thus emulating the example, and equalling the 
generosity of her deceased husband and brother-in- 
law to the Theological Seminary at Princeton. 



58 APPENDIX. 



The late Mr. Hamilton Murray founded Murray 
Hall; and John I. Blair, Esq., of New Jersey, has 
endowed a professor's chair. 

Messrs. Eobert Bonner, Eobert L. Stewart, and 
others, presented the magnificent 21-inch aperture 
telescope, which now, in the hands of the re- 
nowned astronomer, Professor Young, is doing 
good work, and is familiarizing students with the 
mysteries of the universe. 

Physical culture has not been neglected by the 
Pactolian stream; and Messrs. Eobert Bonner and 
Henry G. Marquand, jointly, have erected one 
of the most complete gymnasiums in the country. 

Thus our Alma Mater is strengthened and 
adorned. Let her children, however, not forget 
that her great present need is scholarships, which 
are essential to her full development; and that 
even $100,000 would render an immense service in 
this most important department. 

Note G, Page 34. 

" Description of an Electric Telegraph, and some 
other Electrical Apparatus," by Frances Eonalds. 
8 vo. London: 1823; also see Nature, London, 
November 23, 1871. Vol. 5, p. 59. 

Note H, Page 34. 

" The Electric Magnetic Telegraph," by Law- 
rence Turnbull. 8 vo., 2d Ed. Philadelphia: 
1853, pp. 21, 22. 

Harrison Gray Dyar, an American, set up an 
electric telegraph in 1827, '28, at the race course 



APPENDIX. 59 

on Long Island. Static electricity was used to 
make a record on a strip of moving litmus paper, 
and the alphabet was spelled out by the intervals 
between the sparks passing. lb., 1st Ed., 1852, 
p. 6. 2d Ed., p. 22. 

Note I, Page 35. 

" Schweigger's Journal fur Chemie und Physik." 
1811. Vol. II. , pp. 217, et seq. 

Note K, Page 35. 

This was Bains' English patent. The same sys- 
tem has been several times tried here, but with no 
great success. The Little-Edison " automatic " or 
"fast line " to Washington some years ago, worked 
on this plan ; and more recently the Rapid, and the 
Postal Telegraphs. In all cases, however, an elec- 
tro-magnetic attachment is needed to give the 
alarm, and correct the errors. 

Note L, Page 36. 

Journal of the Society of Arts. July 29, 1S59. 
Vol. VII., pp. 606-7. 

Note M, Page 36. 

Gottingische Gelehrte. Aug. 9, 1834. Part II., 
No. 128, pp. 1272-3. 

Note N, Page 39. 

Faraday had used Henry's quantity magnets in 
his experiments ; but he does not seem to have 
considered the effect of the combination of an 
intensity battery with an intensity magnet, for 



60 APPENDIX. 



distant effects ; having probably overlooked Hen- 
ry's demonstration of that result in Silli man's 
Journal of 1831. Hence his reference to Wheat- 
stone. 

The effect of removing the magnet from the 
battery is stated by Daniells as late as 1843, as an 
elementary truth. He says: " Electro-magnets 
of the greatest power, even when the most ener- 
getic batteries are employed, utterly cease to act 
when they are connected by considerable lengths 
of wire with the battery." (Introduction to the 
Study of Chemical Philosophy ; by Prof. John 
Frederick Daniell, 2d Ed., 1843, chap. XVI., sec. 
859, p. 576.) 

Note 0, Page 39. 

The Electric Telegraph : Was it invented by 
Professor Wheatstone ? By W. F. Cooke. Part 
II. 1856. 

Note P, Page 39. 
lb. Part I., p. 198. 

Note Q, Page 41. 

Professor Henry made a magnet for Yale Col- 
lege — still there— which lifted 2,300 pounds (Silli- 
man's Journal, April, 1831; Vol. XX., p. 201). His 
great Princeton Magnet, now in the Scientific De- 
partment, lifted above 3,000 pounds with a very 
small battery. 



Note E, Page 42. 
Vol. XIX., pp. 403-4. 



APPENDIX. 61 



Note S, Page 43. 

Ingenious men for ages have amused themselves 
in arranging a bi-signal alphabet to obtain the most 
simple system. Bacon, in his great work, " On the 
Dignity and Advancement of Learning,'' Vol. VI., 
ch. 1, 1605, gives an alphabet of two signs, and 
says of it : " This contrivance shows a method of 
expressing and signifying one's mind to any dis- 
tance, by objects that are either visible or audible, 
provided the objects are capable of two differences, 
as bells, speaking trumpets, fire- works and can- 
non," &c. 

In Eees' Cyclopaedia (1802-19) are given various 
illustrations of bi-signal and tri-signal alphabets. 

Gauss and Weber's alphabets in 1S33, and Stein- 
heil's in 1836, are very nearly as simple as possible. 
They use, at most, only four movements, and the 
most frequent letters are represented by only one. 
Two and a- half movements to a letter are needed 
in the best arranged bi-signal alphabet, and these 
old ones probably would not require more. 

Note T, Page 43. 

Philosophical Magazine. March, 1832. Vol. XL, 
p. 190. 

Note U, Page 45. 

Smithsonian Report. 1857. Pp. 111-12. 

Note V, Page 45. 

Steinheil had his telegraph working at Munich, 
in July, 1837, over twelve miles of line, with eight 



62 APPENDIX. 



stations. It was both a sounding and a printing 
telegraph, and used the earth as the return circuit. 
Two bells of different tones gave all the combina- 
tions needed for the alphabet. (Sturgeon's Annals, 
April, 1839, Vol. III., p. 520; Comptes ■ Rendus, 
Vol. VII., pp. 590-93; see also Julius Dup's An- 
wendung des Elektro-magnetismus, Berlin, 1863, 
2d Ed., 1873, sect. 5, pp. 339-347). 

SteinheiFs telegraph was in fact a galvanometer, 
in which the needle was made to swing and strike 
a bell, and to mark a paper by an inking apparatus 
— much like the cable recorder of to-day. It was 
necessarily weak, and quite inferior to Henry's, of 
1831, in which any amount of power can be got, 
and a blow of any strength be delivered. 

Note W, Page 46. 

In the United States, patents are granted only to 
inventors ; but in England they are granted to 
those who "introduce" the inventions into the 
Kingdom, whether they are inventors or not. The 
English system, although not founded on so 
high motives as the United States, is yet pro- 
ductive of more public good, because it stimulates 
enterprising men to seek for valuable improve- 
ments everywhere in the world and introduce them 
into Great Britain, where, perhaps, their authors 
would never come, and where, without a patent, 
no one would be interested in pushing them into 
use. For a long time, in this country, the tele- 
graph patent did not repay its owners for intro- 
ducing it; and no one would have attempted it, or 
persevered in it, unless in the hope of future 



APPENDIX. 



reward, which could not have been got unless 
under the protection of a patent. 

When the Morse patent ran out, he had not 
been adequately rewarded for the expense and 
labor incurred in introducing his special arrange- 
ment into public use, and applied for an extension 
to the Hon. Charles Mason, then Commissioner of 
Patents. Mr. Mason consulted Professor Henry 
on the subject, and he advised the Commissioner 
to grant the extension, although he had been bit- 
terly assailed by Morse and his friends in conse- 
quence of the testimony he had been compelled to 
give in the lawsuit between the owners of the 
patent and infringers. Professor Henry, although 
he thought it derogatory to the dignity of science 
for a scientist to seek for any other reward for his 
discoveries than the consciousness of having done 
good to his fellow-men, and the reputation due to 
his discoveries, yet fully appreciated the wisdom 
of the constitution and laws on the subject of 
patents, and thought that without such a system 
the discoveries of scientists, who devoted them- 
selves to research, would never be made useful for 
man in those practical forms in which inventors 
embody them, and introduce them to the world, 
often with great labor and sacrifice. 

The subjoined letter of Mr. Mason exhibits the 
magnanimous character of Henry. In devotion to 
principle, he recommended an extension of the 
Morse patent, knowing that to reward amply 
those who had introduced the invention to the 
world, would stimulate others to do likewise, al- 
though in doing it he specially benefited those 
who had " despitefully used him." 



64 APPENDIX. 






"United States Patent Office, ) 
March 31, 1856. ) 

"Sir, — Agreeably to your request, I now make 
the following statement : Some two years since, 
when an application was made for an extension of 
Professor Morse's patent, I was for some time in 
doubt as to the propriety of making that exten- 
sion. Under these circumstances, I consulted 
with several persons, and among others with 
yourself, with a view, particularly, to ascertain 
the amount of invention fairly due to Professor 
Morse. The result of my inquiries was such as to 
induce me to grant the extension. I will further 
say that this was in accordance with your express 
recommendation, and that I was probably more 
influenced by this recommendation, and the infor- 
mation I obtained from you, than by any other 
circumstance, in coming to that conclusion. 

"I am, sir, 

"Yours very respectfully, 

"Charles Mason." 

"Prof. J. Henry." 



Note X, Page 50. 

In reversing the galvanic current on the po- 
larized relay used by Henry in Albany, and now 
largely used, the armature is moved both ways by 
magnetism — that is, it strikes the sounder, and is 
withdrawn from it, by magnetism. When the 
current is not reversed, but is broken at each 
signal, magnetism only operates one way, and a 



APPENDIX. 65 



spring is used to withdraw the armature from the 
magnet, where it remains until the next magnetic 
impulse arrives. 

Note Y, Page 54. 

These beautiful and now appropriate verses ap- 
peared in a country newspaper in New Jersey in 
1848. The figure was so striking, and the versifi- 
cation so good, that I remembered them; although 
I regret that the name of their author has escaped 
me. He was a clergyman, and had a parish in 
Pennsylvania. 



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